Socket select error Bad file descriptor (9) after upgrading to master #12285

1. 
   Raulo commented at 11:23 AM on January 28, 2018: none

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   <!-- Describe the issue -->

   After upgrading to master (9cf6393a4f) from 0.15.1 I get the following errors in debug.log

   2018-01-28 11:01:30 socket select error Bad file descriptor (9) 2018-01-28 11:01:30 socket recv error Bad file descriptor (9)

   probably after connecting to some of new peers (it's not clear from the log). These errors were not encountered in 0.15.1.

   These errors do not seem to impact the operation. I guess other peers work.

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   Ubuntu 16.04. GCC (Ubuntu/Linaro 6.3.0-18ubuntu2~16.04) 6.3.0 20170519

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2. fanquake added the label Linux/Unix on Jan 28, 2018
3. 
   Raulo commented at 9:41 PM on January 30, 2018: none

   I'd like to follow up.

   The error has not reappeared even after going back and forth between 0.15.1 and 0.15.99 versions. It seems that the problem was rather caused by problems with reading some old-version files than with peer communication.

   Anybody wanting to debug this problem should make a backup of the 0.15.1 data structure because after rewriting the files, the problem is gone. I had the same error appearing after upgrading testnet so backing up testnet might be an easier path.

4. 
   laanwj commented at 2:27 PM on February 1, 2018: member

   Thanks for the report. looks like many people have this problem, I've created #12323 to track this issue.

5. 
   Raulo commented at 5:49 PM on February 1, 2018: none

   Yes, It's likely related to #12323. I got later also the same leveldb error.

   Unfortunately, I am unable to reproduce this error again. It is either non-deterministic or requires a certain blockchain state I cannot go back now.

6. 
   gmaxwell commented at 9:04 AM on February 4, 2018: contributor

   I think this can be closed now. Thanks for the report!

7. MarcoFalke closed this on Feb 4, 2018

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8. MarcoFalke added this to the milestone 0.16.0 on Feb 4, 2018
9. MarcoFalke locked this on Sep 8, 2021

Milestone
0.16.0